Related Experiment Video
Updated: May 12, 2026
10:28
Repressing Gene Transcription by Redirecting Cellular Machinery with Chemical Epigenetic Modifiers
Published on: September 20, 2018
Polycomb-mediated 3D chromatin interactions in gene regulation.
Sumin Kim1, Miles K Huseyin1, Anders S Hansen1
1Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Gene Regulation Observatory, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; The Novo Nordisk Foundation Center for Genomic Mechanisms of Disease, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Koch Institute for Integrative Cancer Research, Cambridge, MA 02139, USA.
Current Opinion in Genetics & Development
|February 19, 2026
Summary
The Polycomb repressive system uses 3D chromatin interactions to regulate genes. This review explores how these interactions form and contribute to gene repression during development.
Area of Science:
- Molecular Biology
- Developmental Biology
- Genetics
Background:
- The Polycomb repressive system is a crucial chromatin-based transcriptional regulator in multicellular organisms.
- Polycomb-group proteins are known to modify histones and organize 3D chromatin structures.
- The link between histone modifications and gene repression by Polycomb is established, but the role of 3D interactions is unclear.
Purpose of the Study:
- To review current understanding of Polycomb-mediated 3D chromatin interaction formation.
- To discuss potential mechanisms by which these interactions regulate gene expression.
- To highlight knowledge gaps in Polycomb-dependent gene regulation.
Main Methods:
- Literature review of studies on Polycomb repressive system.
- Analysis of research on chromatin structure and gene regulation.
- Synthesis of findings on histone modifications and 3D genome organization.
Main Results:
- Polycomb-group proteins organize specific 3D chromatin interactions.
- These interactions are implicated in stable gene silencing.
- Mechanisms involve looping and tethering of regulatory elements.
Conclusions:
- Polycomb-mediated 3D chromatin interactions are critical for developmental gene regulation.
- Understanding these interactions provides insights into epigenetic control.
- Further research is needed to fully elucidate the functional contribution of 3D interactions to Polycomb gene repression.
Related Concept Videos
01:01Euchromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions take up more dye, appearing darker, while the less-compact areas take up less dye and appear lighter. Based on the compaction level, chromatins are classified into two primary forms – euchromatin and heterochromatin.
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
02:35Chromatin Position Affects Gene Expression
Chromatin is the massive complex of DNA and proteins packaged inside the nucleus. The complexity of chromatin folding and how it is packaged inside the nucleus greatly influences access to genetic information. Generally, the nucleus' periphery is considered transcriptionally repressive, while the cell's interior is considered a transcriptionally active area.
Topologically Associated Domains (TADs)
The 3-dimensional positioning of chromatin in the nucleus influences the timing and level of...
Topologically Associated Domains (TADs)
The 3-dimensional positioning of chromatin in the nucleus influences the timing and level of...
02:33Combinatorial Gene Control
Combinatorial gene control is the synergistic action of several transcriptional factors to regulate the expression of a single gene. The absence of one or more of these factors may lead to a significant difference in the level of gene expression or repression.
The expression of more than 30,000 genes is controlled by approximately 2000-3000 transcription factors. This is possible because a single transcription factor can recognize more than one regulatory sequence. The specificity in gene...
The expression of more than 30,000 genes is controlled by approximately 2000-3000 transcription factors. This is possible because a single transcription factor can recognize more than one regulatory sequence. The specificity in gene...
02:38Heterochromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions that take up more dye are called heterochromatin. Heterochromatin is further classified into two forms – constitutive heterochromatin and facultative heterochromatin.
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
01:01Euchromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions take up more dye, appearing darker, while the less-compact areas take up less dye and appear lighter. Based on the compaction level, chromatins are classified into two primary forms – euchromatin and heterochromatin.
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
02:38Heterochromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions that take up more dye are called heterochromatin. Heterochromatin is further classified into two forms – constitutive heterochromatin and facultative heterochromatin.
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...